wondering if anyone can help me out, i have a 89 civic si hatch with a d16z engine, it also has a t25 turbo installed and other accesiores... my check engine light would come on after about 10 mins. of driving the car, i have put about 4 check valves on the map sensor vaccum line, but someone told me that I would need more. is there something else that is setting off the map sensor code light? what should I do to fix the problem, I also found something on inlinepro.com for the mapsensor problem, but was wondering if anyone knew how that would work? one other thing,...my rpm sometime is really high, especially when I am on the highway, I'll be at 70mph and the rpm would be around 6k and it looks like it wants to jump back to 4k...sometimes it'll jump back to normal and sometimes it won't. like it wants to go back and fourth, etc. it only does this sometimes..could it be the distributor? well thanks for anyones help and knowledge on this.